Oppo starts rolling out a security patch for the month of September 2021 for OPPO Reno 4 with RAM Expansion. The Reno Series of Oppo is considered a premium range of smartphones from Oppo.
Oppo Reno 4 was released on August 05 ,2020 with Android 10, out of the box.
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Ram expansion technology allows devices to have more RAM than it actually does by using Internal Storage (ROM). This is useful for systems, where upgrading internals is not an option.

Source >>Twitter
| Android OS | Update | Release Date/Status | Estimated Months |
| Android 10 | Out-of-the-box | August 2020 | Nil |
| Android 11 | First OS update | May 2021 | 9 months |
| Android 12 | Second/Last OS update | Expected | - |
The OPPO provides 2 years of major OS updates with 3 Years of Security Updates
Hence, the OPPO Reno 4 Android 11 Update is the first major OS update on this device.
Once the update is available on your device, you can head over to Settings >> About Phone >> Software Update section to update your Oppo Reno 4 Pro with the September 2021 Update.
For more Oppo Android updates please download our Android App – Available on the Play Store